Nickel electroplating



United States Patent M 3,484,345 NICKEL ELECTROPLATING Raymond F. Nambride, Paris, France, assignor to Enthone, Incorporated, West Haven, Conn., a corporation of Connecticut No Drawing. Filed Feb. 7, 1967, Ser. No. 614,402

Int. Cl. C23b 5/46, 5/08 US. Cl. 204-49 27 Claims ABSTRACT OF THE DISCLOSURE This invention relates to electroyltic nickel plating and more particularly to new and improved baths and method for the electroplating of bright, level nickel deposits. Additionally this invention is concerned with brightness and leveling additive compositions for nickel electroplating baths.

In accordance with the present invention, it has been found that bright, level nickel electrodeposits are obtained on the object, article or surface being plated by adding or incorporating into the acidic aqueous nickel electroplating solution an effective amount of one or more reaction products of an aldehyde hereinafter specified with a nuclear substituted heterocyclic nitrogen-containing compound of the formula wherein R and R separately are each hydrogen and taken together are R-C=O wherein R is from the group consisting of lower alkyl,

alkenyl, lower alkynyl, hydroxymethyl, trichloromethyl, furfuryl, i.e.

3,484,345 Patented Dec. 16, 1969 and carboethyl, ie.

H Boomera- The nickel plating bath solution herein also contains nickel sulfate and/or nickel chloride, preferably both such nickel salts, water, and preferably a buffering agent, with boric acid the preferred buffering agent. The reaction product or products herein of the aldehyde and substituted heterocyclic nitrogen-containing compound give good results as a brightener and especially good results as a leveler.

The aldehydes of the formula supra include, for example, propargylic aldehyde, chloral, furfural, acetaldehyde, butyraldehyde, propionaldehyde, valet-aldehyde, acrolein, citronellal, crotonaldehyde, tiglaldehyde, glycolaldehyde, and succinaldehyde. Citronellal is a mixture of the stereoisomeric aldehydes:

H I oH2=ownnomomongomom orI2o=o and The exemplary lower alkyl aldehydes set forth supra are characterized by being l-4C alkyl aldehydes, and the exemplary alkenyl aldehydes by having monoor di-olefinically unsaturated alkenyl groups with from 2-9 carbon atoms in the alkenyl group. Any lower alkynyl aldehyde is utilizable herein for reaction with the substituted heterocyclic nitrogen-containing compound to obtain the additive compounds herein, and by lower alkynyl as used herein is meant mono-acetylenically unsaturated alkynyl having from 2-8 carbon atoms in the alkynyl group. The lower alkynyl aldehydes are the preferred aldehydes herein with propargylic aldehyde being preferred among such aldehydes, for reaction with the preferred nuclearsubstituted nitrogen-containing heterocyclic compounds hereinafter disclosed, for obtaining the preferred reac-- tion product additive compounds herein.

Exemplary of the nuclear substituted heterocyclic ni trogen-containing compounds are wpicoline or a-methyb pyridine CH 11% l-CH3 N 'y-picoline or 'y-methylpyridine quinaldine or Z-methylquinoline and aq-lutidine, a,a-lutidine and lipidine or 4-methyl-- quinoline. The ot-methylpyridine, 'y-methylpyridine. and 2- methylquinoline are the preferred nuclear substituted nitrogen-containing heterocyclics for reaction with the preferred aldehydes previously disclosed herein to obtain the preferred reaction product additives herein.

The methyl group or groups of the nuclear substituted heterocyclic nitrogen-containing compounds herein are preferably linked to the alpha ring carbon and/ or gamma ring carbon, relative to the ring nitrogen atom, which correspond to the 2 and 4 positions. Methyl groups linked to the ring carbons in such positions are very reactive.

The reaction product of the aldehyde and the substituted heterocyclic nitrogen-containing compound containing the pyridine ring herein is added or incorporated into the nickel electroplating bath herein in an effective amount, sufficient to obtain bright, level nickel electrodeposits. The effective amount added to the nickel electroplating bath or solution to obtain such results is usually a minor amount, preferably from about 5-200 milligrams of such reaction product or products per liter of the nickel electroplating bath or solution. Instead of the addition to the plating solution of the reaction product or products of a single aldehyde with a single heterocyclic nitrogen-containing compound, the reaction product or products of two or more aldeyhdes herein with one or more of the heterocyclic nitrogen-containing compounds herein can be added to the plating solution as the brightening and leveling additive.

The aldehyde herein reacts with the nuclear substituted heterocyclic nitrogen-containing compound in accordance with the following:

wherein R, R R and m are as aforesaid. The substituent containing the hydroxyl radical of the Type I compound or the substituent containing the olefinic double bond of the Type II compound are preferably linked to the alpha or gamma carbon with respect to the nitrogen of the cyclic nucleus, and the methyl group substituent when present is linked to that alpha or gamma carbon of the cyclic nucleus not bonded to the hydroxy-or olefinic double bond-containing substituent. The last-mentioned methyl group substituent when present can be the -CH group as such or the CH CHOH-R or CH=CH-R group (wherein R has the meaning aforesaid) resulting from the reaction of the di-methyl substituted heterocyclic nitrogen-containing compound with the aldehyde. And by such -CH group substituent when present in the Type I or Type II reaction product compound herein is meant either the CH group per se, the CH CHOH--R group, or the --CH=CHR group, wherein R has the meaning aforesaid. The condensation reaction of the substituted heterocyclic nitrogen-containing compound and the aldehyde to produce the hydroxylated compound of Type I, is effected at temperature usually in the range of about 20 C.-40 C. The intra-molecular dehydration of the Type I compound to form the compound of Type II having the olefinically unsaturated nuclear substituent occurs at higher temperature usually in the range of about 60 C.- 100 C. The reaction product that is added to or incorporated into the nickel plating bath herein is either the Type I compound supra or the Type II compound supra, or a mixture of the Type I and Type II compounds when the temperature of the reaction mixture has first been within the lower temperature range aforesaid for the Type I compound, and subsequently reaches for an 4 insufiicient time to convert all Type I compound to Type II compound the higher range of temperature aforesaid for the Type II compound. The following equations set forth the reaction of a-picoline and the aldehyde to form the Type I compound and the intramolecular dehydration of the Type I compound to form the Type II compound:

supra is added to a nickel electroplating bath such as, for example, that containing:

G./l. NiSO 250-400 NiCl 10-200 H 10-40 and the nickel electrodeposit obtained by electrolyzing the bath between the anode and cathode, with the metallic surface or article to be plated the cathode, at a bath temperature usually in the range of about 20 C.70 C., preferably about 60 C., a current density in the range of usually about 10-100 amperes per square foot, preferably about 50' a.s.f., a bath pH (electrometric preferably between 3.0 and 5.5, and with preferably cathode agitation or compressed air agitation of the electrolyte in the vicinity of the cathode.

Exemplary of the Type I and Type II compounds herein are set forth hereafter. These compounds are added to the nickel plating bath singly, i.e. either the Type I or Type II compound separately, or as a mixture of the Type I and Type II compounds.

-CHzCHOHC Ola Product of reaction between a-methylpyridine and chloral Type II Type I Type I (1711:0110 Cl: Type II [E Type I Product of reaction between 2-methylquino1ine and chloral Type II -on=ono on N/ Type I I N)-CHzCHOHC CH Product of reaction between a-methylpyridine and propargylic aldehyde Type I C'JH=CHO CH Type II 0 Type I Product of reaction between Z-methylquinoline and propargylic aldehyde Type II Type I Product of reaction between u-methylpyridine and furfural Product of reaction between 'y-methylpyridine and furfural Type II Type I II CHzCHOH-C H Product of reaction between Z-methylquinoline and fur fural Type I I N CHzCHOHOHa:

Product of reaction between u-methylpyridine and acetaldehyde Type II i on=onom Type I CHzGHOHCI-Ix Product of reaction between a-methylpyridine and acetaldehyde Type II CH OHCI-Ia Type I Product of reaction between u-methylpyridine and butyraldehyde Type II N CH=CHCH2CH2GH3 CH2CHOHCH2CH2CH3 Type I Product of reaction between a-methylpyridine and butyraldehyde Type I 7 Product of reaction between u-methylpyridine and acrolein Type II I CH=CH-C1I=CII2 N OHZCHOIICII=CH2 Type I Product of reaction between a-rnethylpyridine and acrolein Type II O-CHgCHO CHCH2(CH3) CHCH2CH2CH2(CII3) C=CH L Nj-CH CHOHCHACHQ CHCH2CH2CH=C (CH3):

Product of reaction between a-methylpyridine and citronellal TypeI Type I (IJH CHOHCHACHS) CHCII2CH;CH:C(OI-Ia)z Product of reaction between a-methylpyridine and citronellal I Egon: QHzCHOHUCHa Product of reaction between a-rnethylpyridine and tiglaldehyde Type I LN CHzCHOHCH=CHCHa Product of reaction between rx-methylpyridine and crotonaldehyde Type I (IJH CHOIICH=CHCH Q Product of reaction between -methylpyridine and crotonaldehyde TypeII oH=cHcH=CHCH3 3 TypoI CHQCHOHOH2OH Product of reaction between a-rnethylpyridine and glycolaldehyde Type II \N//-CH=CHCHZOH 'IypeI $HzCHOHCHzOH Product of reaction between 'y-methylpyridine and glycolaldehyde Type II Type I CH=CHOH2OH Product of reaction between a-methylpyridine and succinaldehyde Type II Type I ll CHzCHOHCHzCHzCH Product of reaction between 'y-methylpyridine and succinaldehyde Type II Type I H OH: GHCHzCHzGH CHzCHOHCH;

Product of reaction between Z-methylquinoline and acetaldehyde Type II Type I omononomomorra N/ Product of reaction between Z-methylquinoline and butyraldehyde Type II Type I NJ CH= CHCHzOHzOHs cmononon= GHQ Product of reaction between Z-methylquinoline and acrolein Type II Type I N CI'IzCHOHCH2(CHa) CHCHzCHaCHKCHa) C= CH2 N CHzCHOHOHz(CHa) OHCHzCHzCH=C(CHs)2 Product of reaction between 2-methylquino1ine and citronellal Type II N CH= CHOH2(CH3) CHCHZCHzCHACHa) C= CH2 N CH= CIICH2(OH CHCH2CH CH= C(CH3);

yp I I 0510113 emorronciorn Product of reaction between Z-methylquinoline and Product of reaction between Z-methylquinoline and crotonaldehyde Type II N OH=CHCH=OHCH Type I GHzCHOHCHzDH Product of reaction between Z-methylquinoline and glycolaldehyde.

Type 11 i CII=CIIOH2OII Type I I H \N OHzCHOHCHzCHaCH Product of reaction between Z-methylquinoline and succinaldehyde Type II II oH=orrcn20moH The foregoing enumeration of the Type I and Type II reaction products is exemplary and a partial listing only in the interest of avoiding prolixity.

The substituted heterocyclic compound reaction product or products of the aldehyde and nuclear-substituted nitrogen-containing heterocyclic compound can be added to the nickel plating bath either as such, or when combined or mixed together with an inert diluent or carrier as an additive agent or composition. By inert is meant a diluent or carrier which is compatible and non-reactive or substantially non-reactive with the other constituents of the additive composition and electroplating bath to the material detriment of the additive and bath. The diluent or carrier may or may not itself have a function in the plating bath. Exemplary of the inert diluent or carrier is an inert liquid solvent such as, for instance, an aqueous liquid, e.g. water. However any inert liquid solvent which is compatible with the other ingredients of the electroplating bath can be utilized. An inert solid diluent or carrier can also be employed, for instance, sodium lauryl sulfate as powder, crystals or flakes, and which functions as an anti-pit, or saccharin in powder or crystal form and which functions as stabilizer for the bath. The amounts of the nuclear substituted heterocyclic compound reaction product or products and diluent or carrier in such additives can be varied over wide ranges, for instance a weight ratio of diluent to reaction product or total reaction products within the ratio range of about 40:1 to 3:1 respectively.

The reaction product of the aldehyde and substituted heterocyclic nitrogenrcontaining compound is preferably utilized in the nickel electroplating bath herein in combination with another or second brightening agent, which cooperates with such reaction product brightening agent in producing bright nickel deposits which are ductile as well as level. As the second or cooperating brightening agent is one or more of an organic sulfurand oxygencontaining compound. Exemplary of such organic sulfurand oxygen-containing compounds are aryl sulfonic acids and sulfonates, aryl sulfonamides and sulfonimides, mononuclear aryl sulfinic acids, unsaturated aliphatic sulfonic acids, heterocyclic sulfonic acids, and aryl sulfones. The aromatic or aryl sulfonic acids and sulfonates include both mononuclear and binuclear aryl sulfonic acids and sulfonates, with the aryl radical being of the benzene or naphthalene series. The sulfonates include the mono-, diand tri-sulfonates of the benzene and naphthalene series of compounds. Exemplary of such organic sulfur compound brighteners are benzene monoand disulfonic acids, 1,5-naphthalene disulfonic acid, 2,7-naphthalene disulfonic acid, 1,3,6-naphthalene trisulfonic acid, sodium benzenemonosulfonate, sodium metabenzene disulfonate, the sodium salts of 1,5-naphthalene disulfonic acid and of 2,7-naphthalene disulfonic acid, p-toluenesulfonamide,

benzene monosulfonamide, p-chlorobenzenesulfonamide,

xylene snlfonarnide, 2,4,6-trichlorodibenzenesulfonamide, o-benzoyl sulfonimide, o-toluene sulfonimide, diphenylsulfone, thiophene sulfonic acid, allyl sulfonic acid, vinyl sulfonic acid, benzene sulfinic acid and p-toluene sulfinic acid. Such organic sulfurand oxygen-containing com- I pound brighteners are plating solution-soluble and are utilized in the nickel electroplating baths herein in amounts usually within the range from about 0.1 to 25 grams per liter, preferably from about 0.2 to 7 grams per liter.

The following Examples IVII in the table hereafter set forth and Examples VIII-XXIII which follow the table are illustrative and non-restrictive of aqueous nickel electroplating baths of this invention which achieve bright level nickel electrodeposits. The numerical values in EX- amples I-VII in the table designate grams per liter for the nickel salts, grams per liter for the H BO grams per liter for the saccharin, grams per liter for the organic sulfurand oxygen-containing compound brightener cooperative with the brightener additive compound of this invention, grams per liter for the sodium lauryl sulfate, and milligrams per liter for the brightener additive compounds, i.e. the Type I and/or Type II reaction product, of this invention. The sodium lauryl sulfate is an antipitting agent, and the saccharin is a bath stabilizer.

Nickel Electroplating Bath I NiSOi.7I-I20.. NiClzJSHzO-.. HaBOa Saccharin. 0.5 Organic sulfurand oxygen-containing compound brightener cooperative with the Type I and/or Type II brightener herein. Stfiillln'l lauryl sulfate p Temperature, C" Type I and/or Type II product of reaction of chloral with cit-methylpyridine Type I and/or Type II product of reaction of propargylic aldehyde with a-niethylpyridine Type I and/or Type II product of reaction of furfural with a-methylpyridine Type I and/or Type II product of reaction of chloral with a-methyl pyridine Type I and/or Type II product of reaction of propargylic aldehyde with a-methylpyritline Type I and/or Type II product of reaction of turlural with a-methylpyridine 100 Type I and/or Type II product of reaction of chloral with ll-methylquinoline Type I and/or Type II product of reaction of propargylic aldehyde with 2-n1ethylquinoline Type I and/or Type II product of reaction of furtural with 2-1nethylquinoline The organic sulfurand oxygen-containing compound brightener cooperative with the Type I and/or Type II brightener herein of Examples I-VII of the table and of Examples VIII-XXIII hereafter set forth is the condensation reaction product of the bishydroxyethylether of 2-butyne-1,4-diol and naphtho-1,8-sultone disclosed in copending US. Patent application Ser. No. 500,462, filed Oct. 1, 1965. In place of this cooperating brightener, however, any of the other cooperating brighteners previously disclosed herein can be utilized with good results. The use in Examples I-XXIII of an anti-pit such as sodium lauryl sulfate or another anti-pit is preferred but not essential, and the use in such examples of saccharin is also preferred but not essential.

EXAMPLE VIII NiSO 71-1 0 grams/liter 330 NiCl 6H O do 80 H BO do 40 Saccharin d0 0.5

Organic sulfurand oxygen-containing compound brightener cooperative with the Type I and/or Type II brightener herein grams/liter 0.5 Sodium lauryl sulfate do 0.2 Type I and/ or Type II product of reaction of acetaldehyde with a-methylpyridine milligrams/liter" 50 EXAMPLE IX NiSO -7H O grams/liter 330 NiCl '6H O do 80 H3BO3 dO Saccharin do 0.5 Organic sulfurand oxygen-containing compound brightener cooperative with the Type I and/or Type II brightener herein grams/liter 0.5 Sodium lauryl sulfate do 0.2 Type I and/or Type II product of reaction of hutyraldehyde with a-methylpyridine mi.lligrams/liter 35 Organic sulfurand oxygen-containing compound brightener cooperative with the Type I and/or Type II brightener herein "grams/liter 0.6 Sodium lauryl sulfate do 0.5 Type I and/ or Type 11 product of reaction of valeraldehyde with a-methylpyridine milligrams/liter 45 EXAMPLE XI NiSO -7H O grams/liter.... 330 NiCl -6H O- do. 80 H3BO3 Saccharin do 0.5 Organic sulfurand oxygen-containing compound brightener cooperative with the Type I and/or Type II brightener herein grams/liter 0.5 Sodium lauryl sulfate do 0.2 Type I and/or Type II product of reaction of acrolein with a-methylpyridine milligrams/liter 60 EXAMPLE XII NiSO -7H O grams/liter 330 NiCl -6H O do 80 H3BO3 d Saccharin "do"..- 0.5 Organic sulfurand oxygen-containing compound brightener cooperative with the Type I and/or Type II brightener herein grams/liter. 0.5 Sodium lauryl sulfate do 0.2 Type I and/ or Type II product of reaction of crotonaldehyde with a-methylpyridine milligrams/liter 40 EXAMPLE XIII NiSO -7H O grams/liter 300 NiC1 -6H O do 80 H3BO3 .dO Sodium lauryl sulfate do 0.5 Type I and/or Type II product of reaction of tiglaldehyde with a-methylpyridine milligrams/liter 10 EXAMPLE XIV NiS0 -7H O -..grams/liter 330 NIC12 --dO 1 1 130 do 40 Saccharin do.. 0.5 Organic sulfurand oxygen-containing compound brightener cooperative with the Type I and/ or Type II brightener herein "grams/liter..- 0.5 Sodium lauryl sulfate do 0.2 Type I and/or Type II product of reaction of glycolaldehyde with a-methylpyridine milligrams/liter..- 150 Type I and/ or Type II product of reaction of succinaldehyde with a-methylpyridine milligrams/liter 175 14 EXAMPLE XVI NiSO -7H O grams/liter NiCl -6H O dn H3BO3 Sodium lauryl sulfate do Type I and/ or Type II product of reaction of citro- Organic sulfurand oxygen-containing compound brightener cooperative with the Type I and/ or Type II brightener herein grams/1iter Sodium lauryl sulfate do Type I and/ or Type II product of reaction of butyraldehyde with Z-methylquinoline milligrams/liter-..

EXAMPLE XIX NiSO -7H O ..grams/liter NiCl -6H O rlo H3BO3 Saccharin do Organic sulfurand oxygen-containing compound brightener cooperative with the Type I and/ or Type II brightener herein grams/liter Sodium lauryl sulfate do Type I and/or Type II product of reaction of acrolein with Z-methylquinoline milligrams/liter EXAMPLE XX NiSO 7H O grams/liter NiCI 6H O do H BO do Saccharin do Organic sulfurand oxygen-containing compound brightener cooperative with the Type I .and/ or Type II brightener herein grams/liter Sodium lauryl sulfate do Type I and/ or Type II product of reaction of crotonaldehyde with 2-methylquinoline milligrams/ 1iter EXAMPLE XXI NiSO -7H O grams/liter.. .....dO....... H BO do.. Saccharin do Organic sulfurand oxygen-containing compound brightener cooperative with the Type I and/ or Type II brightener herein grams/liter Sodium lauryl sulfate do Type I and/or Type II product of reaction of tiglaldehyde with Z-methylquinoline milligrams/ 1iter 1 EXAMPLE XXII NiSO -7H O grams/liter 330 NiCl '6H O do 80 H3BO3 d0 Saccharin do 0.5 Organic sulfurand oxygen-containing compound brightener cooperative with the Type I and/ or Type II brightener herein grams/liter 0.5 Sodium lauryl sulfate do 0.2 Type I and/ or Type II product of reaction of glycolaldehyde with Z-methylquinoline milligrams/liter 130 EXAMPLE XXIII NiSO -7H O grams/liter 330 NiCl -6H O do 80 H BO do 40 Saccharin do 0.5 Organic sulfurand oxygen-containing compound brightener cooperative with the Type I and/ or Type II brightener herein grams/liter 0.5 Sodium lauryl sulfate do 0.2 Type I and/ or Type II product of reaction of succinaldehyde with 2-methylquinoline milligrams/liter 90 The aqueous baths of Examples I-XXIII supra are utilizable for electrodepositing bright level nickel deposits which are firmly adherent deposits under the plating conditions including current density, bath temperature and pH previously set forth herein.

What is claimed is:

\1. A nickel electroplating bath comprising an acidic aqueous solution of at least one nickel salt from the group consisting of the sulfate and chloride of nickel and an effective amount as brightener and leveler of at least one nuclear substituted nitrogen-containing heterocyclic compound selected from the group consisting of those of the formulae:

wherein R is selected from the group consisting of lower alkyl, alkenyl, lower alkynyl, hydroxymethyl, trichloromethyl, furfuryl and carboethyl.

R and R separately are each hydrogen and taken together are:

I-IC o I H and m is an integer from 0 to 1, m being zero when R and R taken together are as aforesaid, all substituents of said nuclear-substituted heterocyclic compound being linked to carbon atoms of the heterocyclic nucleus.

2. The solution of claim 1 wherein the R-containing substituent of the nuclear-substituted nitrogen-containing compound is linked to the alpha or gamma ring carbon atom relative to the ring nitrogen atom, and the methyl group substituent when present is linked to the alpha or gamma ring carbon atom not linked to said R-containing substituent.

3. The solution of claim 2 further characterized by containing another brightening agent which cooperates with the first-mentioned brightening agent, said other brightening agent being an organic sulfurand oxygencontaining compound brightener selected from the group consisting of aryl sulfonic acids, aryl sulfonates, aryl sulfonamides, aryl sulfonimides, mononuclear aryl sulfinic acids, unsaturated aliphatic sulfonic acids, thiophene sulfonic acid and diphenyl sulfone.

4. The solution of claim 3 wherein R of the formulae is lower alkynyl.

5. The solution of claim 4 wherein R of the formulae is propargyl.

6. The solution of claim 3 further characterized by containing both nickel sulfate and nickel chloride in the solution.

7. The solution of claim 6 further characterized by containing a buffering agent therein.

8. The solution of claim 7 wherein the buffering agent is boric acid.

9. The solution of claim 3 wherein the substituted nitrogen-containing heterocyclic compound is present in the solution in amount of about 520() milligrams per liter.

10. The solution of claim 3 wherein R of the formulae is lower alkyl,

11. The solution of claim 3 wherein R of the formulae is alkenyl.

12. A method for electroplating bright nickel deposits comprising passing a current through an acidic nickel plating bath between an anode and cathode, the nickel bath comprising an acidic aqueous solution of at least one nickel salt selected from the group consisting of the sulfate and chloride of nickel, and an effective amount as brightener and leveler of at least one nuclear-substituted nitrogen-containing heterocyclic compound selected from the group consisting of those of the formulae:

wherein R is selected from the group consisting of lower alkyl, alkenyl, lower alkynyl, hydroxymethyl, trichloro methyl, furfuryl and carboethyl, R and R separately are each hydrogen and taken together are:

I IIG and m is an integer from 0 to l, m being zero when R and R taken together are as aforesaid, all substituents of said nuclear-substituted heterocyclic compound being 'fonic acid and diphenyl sulfone.

1 7 ates with the first-mentioned brightening agent, said other brightening agent being an organic sulfurand oxygencontaining compound brightener selected from the group consisting of aryl sulfonic acids, aryl sulfonates, aryl sulfonamides, aryl sulfonimides, mononuclear aryl sulfinic acids, unsaturated aliphatic sulfonic acids, thiophene sul- 15. The method of claim 14 further characterized by the nickel plating bath containing both nickel sulfate and nickel chloride.

16. The method of claim 14 wherein R of the formulae is lower alkynyl and the nuclear substituted heterocyclic nitrogen-containing compound is selected from the group consisting of a-methylpy ridine, -methylpyridine and 2- methylquinoline.

17. The method of claim 16 wherein R of the formulae is propargyl.

18. The method of claim 14 wherein R of the formulae is lower alkyl.

19. The method of claim 14 wherein R of the formulae is alkenyl.

20. The solution of claim 3 wherein the said first-mentioned brightening agent is at least one compound selected from the group consisting of those of the formulae:

and

oH=oHo E on N 21. The solution of claim 3 wherein the said first-mentioned brightening agent is at least one compound selected from the group consisting of those of the formulae:

(fHzCHOHO OH and CH=OHC CH i N -CHzOHOHO CH @OH=OHCECH and 23. The solution of claim 3 wherein the said first-men tioned brightening agent is at least one compound selected from the group consisting of those of the formulae:

EN CH2OHOHOCl and L CH==CHC 01 24. The solution of claim 3 wherein the said first-mentioned brightening agent is at least one compound selected from the group consisting of those of the formulae:

tioned brightening agent is at least one compound selected from the group consisting of those of the formulae:

and

-0mononoo1,

and

i CH=CHCC11 N 3 26. The solution of claim 9 wherein the organic sulfurand oxygen-containing compound brightener is present therein in amount from about 0.1 to 25 grams per liter.

27. The solution of claim 26 wherein the organic sulfurand oxygen-containing compound brightener is present therein in amount from about 0.2 to 7 grams per liter.

References Cited UNITED STATES PATENTS 2,427,286 9/1947 Knapp et a1. 260 -283 XR 2,647,866 8/1953 Brown 204-49 2,863,802 12/1958 Pyne 260297 XR 2,962,498 11/1960 White et a1. 3,262,906 7/1966 Perry 260--283 XR 3,371,096 2/1968 Brust et a1. 260297 XR 3,400,126 9/1968 Brust et al. 260 -297 XR FOREIGN PATENTS 897,401 5/ 1962 Great Britain.

PATRICK P. GARVIN, Primary Examiner UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No 3 ,484 345 December 16 1969 Raymond F. Nambride It is certified that error appears in the above identified patent and that said Letters Patent are hereby corrected as shown below:

Column 1, lines 36 to 40 that portion of the formula reading "=CH should read CH lines 68 to 71,

HC CH HC CH I! II H H HC C- should read HC\ /C- Column 6, line 61, "omethylpyridine" should read y-methylpyridine Column 7, line 14, "a-methylpyridine" should read methylpyridine lines 22 to 27, cancel the formula; lines 28 to 32 that portion of the formula reading "-CH CHOCHCHZ (CH3) CHCH2CH2CH2(CH3)C=CH2" should read CHzCHOI-ICH (CH3)CHCH CH2CH (CH )C=CH lines 44 to 48 that portion of the formula reading "CH=CHCH (CH )CHCH CH CH=[CH should read CH=CHCH (CH CHCH CH CH=C(CH 2 line 6%, "u-methylpyridine" should read ymethylpyridine Column 15 line 54 "carboethyl should read carboethyl Column 16 lines 45 to 49 the formula should appear as shown below:

H=CHR Column 3, lines 27 to 30 the formula should appear as shown belo (CHSJIH Column 17, line 12, "alkynyl and the nuclear substituted heterocyclic nitrogen-containing compound is selected from the group consisting of a-methylpyridine y-methylpyridine and 2- methylquinoline. should read alkynyl n Signed and sealed this 3rd day of November 1970 (SEAL) Attest:

EDWARD M.FLETCHER,JR. WILLIAM E. SCHUYLER, JR. Attesting Officer Commissioner of Patents 

